Deputy Secretary General and Political Director of the European External Action Service, Enrique Mora, addresses the media in front of the Grand Hotel Vienna where closed-door nuclear talks take place in Vienna, Austria, on June 20, 2021. AP
The talks were adjourned nearly a week ago after a round marked by tensions over new demands from Tehran. They are chaired by EU diplomat Enrique Mora.
The EU said participants from Britain, France, Germany, China, Russia and Iran will resume their efforts on Monday. They had been interrupted to allow Iran's chief negotiator to return home for consultations.
The United States has participated indirectly in the ongoing talks because it withdrew from the accord in 2018 under then-President Donald Trump. President Joe Biden has signaled that he wants to rejoin the deal.
The accord was meant to rein in Iran's nuclear program in return for loosened economic sanctions.
Following the U.S. decision to withdraw from the deal and reimpose sanctions on Iran, Tehran has ramped up its nuclear program again by enriching uranium well beyond the thresholds allowed by the agreement.
Iran has also restricted monitors from the U.N.'s atomic watchdog agency from accessing its nuclear facilities, raising concerns about what the country is doing out of view.
Diplomats from the three European countries involved said after the talks adjourned last week that negotiators in Vienna are "rapidly reaching the end of the road.'' They have expressed frustration with Tehran's new demands in recent weeks but pointed to "some technical progress'' so far.